Many imaging devices are known for producing medical images of body lumens, such as the gastrointestinal (GI) tract. For example, endoscopy is widely used for observing, photographing tissue, and taking specimens from lesions and the like. In a conventional method of examining a colon using an endoscope, for example, the endoscope is typically manually inserted into the colon. In this manual technique, patients may often complain of abdominal pain and distention because the colon is extended or excessively dilated, thereby necessitating stopping the endoscopic procedure. Furthermore, it is not unusual for the colon to bleed and be accidentally perforated. Insertion of an endoscope through the sigmoid colon and into the descending colon, or through the splenic flexure, the transverse colon, the hepatic flexure or parts affected by previous operations may also be accompanied with difficulty. Because of these reasons, a colonoscopy is typically performed by a relatively small number of skilled practitioners, and the rate of patient pain and discomfort is high.
U.S. Pat. No. 5,337,732 to Grundfest et al., whose disclosure is incorporated herein by reference, describes a robot for performing endoscopic procedures, which includes a plurality of segments attached to each other through an articulated joint. Actuators can move the segments together and apart and change their angular orientation to allow the robot to move in an inchworm or snake-like fashion through a cavity or lumen within a patient. Inflatable balloons around the segments inflate to brace a temporarily stationary segment against the lumen walls while other segments move. A compressed gas line attached to the back segment provides compressed gas to inflate the balloons and optionally to drive the actuators. The lead segment includes a television camera and biopsy arm or other sensors and surgical instruments.
U.S. Patent Application Publication 2003/0168068 to Poole and Young, whose disclosure is incorporated herein by reference, describes a method for lining a body cavity with a liner that contains two chambers by (a) selectively controlling fluid pressure in a first of the chambers so as cause the first chamber to evert and advance into said body cavity, and (b) selectively controlling fluid pressure in a second of said chambers to control the stiffness of the liner.
U.S. Patent Application Publication 2003/0105386 and U.S. Pat. No. 6,485,409 to Voloshin et al., whose disclosures are incorporated herein by reference, describe endoscopic apparatus comprising an inflatable sleeve, wherein inflating the sleeve causes an endoscope to be advanced into the colon.
U.S. Patent Application Publication 2002/0107478 to Wendlandt, whose disclosure is incorporated herein by reference, describes a self-propelled catheter, wherein pressurizing an everting tube coupled to the catheter advances the catheter into the body.
U.S. Pat. No. 6,702,735 to Kelly, whose disclosure is incorporated herein by reference, describes a device for moving a tool along a passage. The tool is coupled to an inflatable sheath, such that as the sheath is inflated it extends into the passage and carries the tool along.
U.S. Pat. No. 5,259,364 to Bob, et al., whose disclosure is incorporated herein by reference, describes an endoscopic device comprising a flexible eversion tube, wherein inflating the eversion tube causes an endoscope to be advanced into a body cavity.
U.S. Pat. No. 4,403,985 to Boretos, whose disclosure is incorporated herein by reference, describes a catheter containing ports near its distal end through which high pressure fluid is forced to advance and steer the catheter.
U.S. Pat. No. 4,176,662 to Frazer, whose disclosure is incorporated herein by reference, describes an endoscope having a propulsion mechanism and at least one transmitter at the distal end transmitting bursts of energy waves for tracking the position of the distal end. The propulsion mechanism consists of two radially expandable bladders separated by an axially expandable bellows with only the forward bladder attached to the distal end so that by expanding and contracting them in proper sequence, propulsion of the endoscope is achieved.
U.S. Pat. No. 4,148,307 to Utsugi, whose disclosure is incorporated herein by reference, describes a tubular medical instrument having at least one cuff assembly including two cuffs disposed on the circumference of a flexible sheath, spaced at prescribed intervals and made expansible only in a radial direction of the flexible sheath, and a deformable propellant cuff having a doubled-back section, disposed also on the circumference of the sheath between the two cuffs. When air is introduced into, or drawn from, the three cuffs selectively, the flexible sheath automatically advances step-by-step in a human body cavity.
U.S. Pat. No. 5,906,591 to Dario et al., whose disclosure is incorporated herein by reference, describes an endoscopic robot, adapted to be inserted into a body cavity of a patient and to be advanced therein using “inchworm-like” motion.
U.S. Pat. No. 6,007,482 to Madni et al., whose disclosure is incorporated herein by reference, describes an endoscope having a pair of telescoping sections at its distal end, one of which carries a camera, and which are alternately actuated to provide movement through a body passageway by a Bowden type of cable. Respectively attached to the two cylindrical sections are inflatable bladders which provide for the movement.
U.S. Pat. No. 5,662,587 to Grundfest et al., whose disclosure is incorporated herein by reference, describes an endoscopic robot having a plurality of segments attached to each other. Traction segments embrace the walls of a body lumen. Other segments include actuators that cause the endoscope to locally deform its shape via bending, extending, or some combination of bending and extension. A method is provided to sequence the action of the segments to cause “inchworm-like” or “snake-like” locomotion, or a combination of them through a curved and flexible lumen. A compressed gas line attached to the back segment provides compressed gas for insufflation of the lumen, and can optionally be used to drive the actuators that control the operation of the endoscope segments.
U.S. Pat. No. 4,690,131 to Lyddy, Jr. et al., whose disclosure is incorporated herein by reference, describes a combination of elements adapted to be used with an endoscope, and capable of at least partially extending with the instrument into the lumen of a tubular body part, such as the large intestine. A sheath is adapted to be mounted on the endoscope. The endoscope and sheath are provided with selectively inflatable cuffs movable with respect to one another by axially sliding the sheath on the endoscope.
U.S. Pat. No. 4,040,413 to Ohshiro, which is incorporated herein by reference, describes an endoscope comprising a tube having one or more inflatable balloons on an outer surface thereof. A fiber optic bundle passes through the tube to a distal flexible portion of the tube, for viewing an interior of a body cavity. When only one balloon is provided, the balloon is provided on one side of the tube near the end thereof to enlarge the space within a body cavity in one direction so that there is sufficient space in this direction for the flexible portion of the tube to bend in this direction, and to thereby obtain a large field of view. When more than one balloon is provided, one of the balloons is selectively inflated to enlarge the space within the body cavity in the desired direction. In an embodiment, an outer sleeve is provided around the tube with balloons on the outer face thereof and is made slidable with respect to the tube. The outer sleeve and the tube are inserted into the body cavity by alternately inflating the balloons on the outer sleeve and those on the tube to facilitate the insertion thereof into the body cavity.
U.S. Pat. No. 6,503,192 to Ouchi, which is incorporated herein by reference, describes an insertion facilitating device for an intestinal endoscope. The device has a cylindrical body in which an insertion portion of the endoscope is inserted while holding an anal sphincter of a patient in an open position. The cylindrical body is provided at one end thereof with a conical opening. In an embodiment, the cylindrical body is provided on its inner surface with a pressure leakage prevention ring made of a sponge material, for preventing leakage of internal air of the patient's body.
U.S. Patent Application Publication 2003/0083547 to Hamilton et al., which is incorporated herein by reference, describes methods and apparatus for inhibiting longitudinal expansion of a body portion of an endoscopic sheath during inflation of an inflatable member. In one embodiment, a sheath assembly includes a body portion adapted to encapsulate a distal end of an insertion tube, and an inflatable member coupled to the body portion and adapted to be inflated radially outwardly from the body portion. The sheath assembly further includes an expansion-inhibiting mechanism coupled to at least one of the inflatable member and the body portion. The expansion-inhibiting mechanism is described as inhibiting longitudinal expansion of the body portion during inflation of the inflatable member. The expansion-inhibiting mechanism may comprise, for example, a non-compliant member, a longitudinally-stretched portion, a reinforcing spring member, a pressure relief device, or a suitable detent mechanism.
PCT Publication WO 04/069057 to Gobel, which is incorporated herein by reference, describes a device for use in healing processes, comprising a flexible double-walled inflatable tube segment which encloses a hollow space.
U.S. Patent Application Publication 2003/0000526 to Gobel, which is incorporated herein by reference, describes techniques for controlling the breathing gas flow of a ventilator for assisted or controlled ventilation of a patient as a function of the tracheobronchial airway pressure of the patient. The techniques include introducing a ventilator tube, such as a tracheal tube or tracheostomy tube, into the trachea. The tube is subjected to breathing gas, and is equipped with an inflatable cuff and at least one lumen that is continuous from the distal end of the tube to the proximal end of the tube. The tube is adapted to detect the airway pressure by continuous or intermittent detection and evaluation of the intra-cuff pressure prevailing in the cuff of the tube. The breathing gas flow of the ventilator is controlled as a function of the intra-cuff pressure detected.
PCT Publication WO 03/045487 to Gobel, which is incorporated herein by reference, describes a bladder catheter for transurethral introduction into the urinary bladder by the urethrae, consisting of an elastic catheter shank with a fillable balloon element secured thereto and connected to a filling channel incorporated into the wall of the catheter shank. The balloon element and the catheter shank are made of polyurethane, a polyurethane-polyvinylchloride mixture, or similar polyurethane-based material.